When a POI that has sleeper spawners in it is overwritten by something else like air, the sleeper spawners are kept in the chunk and still trigger spawns. Sleeper spawners should be removed when a block at their position got changed.
Right now, adding a prefab multiple times with slightly changed positions will add the sleeper spawners every time, accumulating them all together.
When a POI that has sleeper spawners in it is overwritten by something else like air, the sleeper spawners are kept in the chunk and still trigger spawns. Sleeper spawners should be removed when a block at their position got changed.
Right now, adding a prefab multiple times with slightly changed positions will add the sleeper spawners every time, accumulating them all together.
Same might be true for fixed spawners.